Spring means for holding the operating shaft of a punch in the punch open position



2 Sheets-Sheet l & AR

INVENTOR.

EM. my:

April 1958 A. F. BROOK SPRING MEANS FOR HOLDING THE OPERATING SHAF A PUNCH IN THE PUNCH OPEN POSITION Flled Aprll 14 1955 April 8, 1958 A. F. BROOK 2,829,739

A s F HOLDING T SPRING M HE OPERATING SHAFT OF A NCH THE! PUNCH OPEN POSITION Filed April 14, 1955 I 2 Sheets-Sheet 2 SPRING MEANS FOR HOLDING THE OPERATING SHAFT OF A PUNCH IN THE PUNCH OPEN POSITION Arthur F. Brook, Poughkeepsie, N. Y., assignor to Wire- Corporation, Poughkeepsie, N. Y., a corporation of New York Application April 14, 1955, Serial No. 501,256

1 Claim. (Cl. 188-83) The invention disclosed relates to punches for perforating the sheets used in mechanical binders.

Objects of the invention are to provide 'a simple, inexpensive form of punch which can be made up offew, readily assembled parts and which can be operated by hand to perforate sheets as required for use in such binders.

Special objects of the invention are to assure the positive and accurate operation of a whole row of the punches required for forming the number of perforations usually provided in such sheets.

Further special objects of the invention are to control the punch operation so that the handle used for actuating the multiple punches may be left and will normally be retained in the position ready for use of the punch.

Other desirable objects and novel features through which the purposes of the invention are attained are set forth and will appear in the course'of the following specification.

The drawings accompanying and forming part of the specification illustrate a present commercial embodiment of the invention. Structure, however, may be modified and changed as regards the immediate illustration, all within the true intent and scope of the invention as hereinafter defined and claimed.

Fig. 1 in the drawings is a top plan view of the punch with the operating handle in theupstanding position, ready for immediate use of the machine;

Fig. 2 is a front elevation with portions broken away and appearing in section;

Fig. 3 is an enlarged cross-sectional view as on substantially the plane of line 3-3 of Fig. 1, with the operating handle raised to lift the punch elements and broken lines indicating the lowered position of the handle;

Fig. 4 is a broken sectional view showing the operating shaft rocked to lower the punch elements;

Fig. 5 is a broken plan view of the left-hand end portion of the operating shaft and associated parts;

Fig. 6 is a broken vertical sectional detail on substantially the plane of line 6-6 of Fig. 5, showing the detent spring for holding the shaft and punch elements in open position;

Fig. 7 is a broken plan view of a sheet perforated in the punch.

The body of the machine is shown as comprising a hollow base 9 having a flat table portion 10 at the front and an upright wall or abutment portion 11 across the back, this wall being undercut at the front at 12 to receive the sheets, this undercut terminating in an abrupt sheet gaging edge 13.

Bearings 14 are shown provided at opposite ends of the upstanding ridge or wall 11 rotatably receiving the shaft 15 positioned, as shown in Figs. 3 and 4, with its forward edge overstanding the ridge.

Slidingly mounted in upright bearings 16 in the ridge 11 are the punches 17, as many as may be required to State Patfrflt 0 These punch elements are each free and independent of each other, except for their common connection with the operating shaft 15, and this common connection is such as to permit free and independent selfadjustment of the several punch elements.

In the illustration the punch elements are of plain cylindrical form such as may be cut from rod material, and they are milled at their upper ends on one side to leave round-nosed lugs 20 to enter the longitudinal groove 21 in the adjacent side of the shaft with recessions 22, 23 above and below the lugs for clearance from the shaft.

The lower ends of the punch elements are shown as concaved at 24 to provide sharp cutting edges cooperative with the companion die openings 25 in the base.

Means for rocking the shaft in opposite directions is shown in the form of a rod 26 screwed through the shaft at 27 and having a hand knob 28 on the free end of the same.

To prevent overthrow such as might injure the parts or tend to disconnect the keyed connection between the shaft and plungers, the rod which forms the operating handle is shown as engageable on its down-stroke with a front stop 29 and as having an extended end portion 30, Fig. 3 engageable on the up-stroke with a back abutment 31.

To releasably retain the shaft in the position in which it may be left, and particularly to hold the parts in the open position, Fig. 3, ready to receive the sheets, holding or retaining springs are provided in the illustration positioned to cooperate with the grooved portion of the shaft.

These springs are indicated at 32, Figs. '1, 5 and 6, seated in upright bores or channels 33 provided in the front walls of the bearings 14, said springs comprising flat strips of spring material having their upper ends doubled back to form spring fingers 34 engaging the front portion of the shaft above the groove 21, and their lower ends doubled back at 35 to form spring brake elements engaging the shaft below the groove and below the center of the shaft.

Fig. 6 shows how the lower end portions 35 may be doubled back at 36 into or substantially into full engagement with the fiat back portions 37 so as to form substantially solid abutments engaged below the center of the shaft and thereby held in their seats by the overstanding portion of the shaft.

These flat strip springs with their introverted ends preferably are of a size to closely fit the holes 33 in which they are seated so that they cannot turn away from the shaft. The lower, abutment forming spring fingers 35, 36 will yield sufficiently to permit the springs to be forced down into the bottom of the holes, past the center of the shaft so that these springs, once seated, will be automatically held in place.

The holes 33, as shown in Fig. 6, intersect the forward sides of the bearings and so can be used as passages for lubricating the shaft.

The pressure exerted by the upper spring finger 34 at the upper edge of the groove and against the surface of the shaft above the groove serves to hold the shaft in the position shown in Figs. 3 and 6, with the plungers raised and with the handle 26 in the uplifted position, ready for use of the punch.

The shaft preferably is of relatively large diameter to afford desired rigidity and to provide sufiicient radial offset of the groove 21 to impart the necessary stroke to the punch elements. This will be clear from Figs. 3

and 4, illustrating. the throwof the actuating groove acquired with a relatively short angular movementof the shaft.

ringsv 38. engaged in annular grooves; 39 inthe' sh'aft' ends at outer sides of the bearings '14. Figs. 1- and 2 show how with this construction the-shaft ends need project only slightly beyond the bearings.

In addition to the front gage for the sheets, show at 13, the punch may carry a side gage.

The latter is shown at 40, Figs. 1 and 2, slidingly seated in a groove 4Lprovided in the top of the base and secured in adjusted relation therein by clamp screw 42 extending through slot 43 in the side gage. The location of this gage in a depression below thetablesurface avoids the possibility of sheets being unintentionally slippedbeneath this gage. 4

The hollow base structure is shown in Figs. 3' and 4 as closedat the bottom by a rubber or other elastic pad 44 having a surrounding, inwardly inclined flange portion 45 yieldingly gripped about the lower edge portion of the base. This removable pad provides an enclosure for cuttings struck down through the die openings.

The punch consists of few, simple and easily assembled parts.

.The punches and shaft are operatively connected by simply sliding the shaft endwisethrough one bearing, engaging the lug of one punch after the other in the gro'ovein the shaft until the opposite bearing is reached, whereupon the shaft may be secured against endwise movement, the handle rodbe screwed through the intermediate portion of the shaft and the detent springs then be driven down over the shaft into seated relation in the oil holes. The handle then will be in cooperative rela-' tion with the frontandback stops 29, 31 and the shaft will be tensioned to hold the punches up, ready for punching operations.

The hollow base carrying the bearings for the punches and the bearings for the shaft may be a single casting, requiring a small amount of machining. J

The punches may be of rod or bar stock, round, square or other cross-section, cut to proper length and milled across one end to'provide the shaft engaging lugs 20 and shaft clearances 22, 23 at opposite sides of the lugs.

The groove in the shaft is shown as straight or parallel The shaft is shown as held in its bearings by snap in respect to the axis of the shaft, but this may be inclined or otherwise shaped as to effect sequential or other desired action of the punches. Also, the punches may be of different effective lengths to accomplish sequential operations. Other variations are possible, all within the true scope of the invention.

What is claimed is:

'A self retained spring for holding a longitudinally grooved oscillating punch operating shaft in the punch open position, comprising a spring strip having an intermediate substantially straight fiat back portion and end portions doubled back toward each other at the same side of the back portion and one end portion extended angularly toward and substantially into engagement with the back portion and forming an abutment for holding said doubled end portion spaced away from the back portion, and a support having a bearing opening for the shaft and an intersecting bore extending across one side of said bearing opening, a shaft in said opening, said here being of a diameter only slightly greater than the width of said spring, and said spring being of such dimensions that when the spring is seated in said bore with the doubled back end portions faced toward the bearing opening at points to opposite sides of the center of said bearing opening and in contact with said shaft when said flat back portion is in engagement with the wall of the bore remote from the shaft and said doubled back portions are compressed relative to the flat back portion, and whereby said spring may be forced down in said bore over the side of a shaft journalled in said bearing opening into position with said doubled back end portions in engagement with the shaft at opposite sides of the shaft center and in which position said spring will then be retained in said bore by said shaft.

References Cited in the file of this patent UNITED STATES PATENTS 

